At the end of the game, the King and the Pawn goes into the same box

Scalar – better calculator for iPhone July 13, 2013

Why limit yourself to one line display of cheap pocket calculators when your iPhone or iPad can do much more? Scalar gives you an endless sheet of paper you can calculate on so you’ll never lose track again, even with the most complex calculations.
Your calculations are automatically saved when you leave the app and you can share them by email.
Features:
* editable entries, the app recalculates everything as you type
* entries could be referenced from each other for very complex calculations
* arbitrary precision numbers
* percentages
* e-mail integration
* copy/paste in calculations
* saves last calculation between launches
* tap and hold backspace to clear whole calculation

I like the fact that they display all the calculations that I do so that I know if my made any mistake in typing the number.